Polybasic aliphatic acto-polyhydbic



Patented Dec. 8, 1936 UNlTED STATES POLYBASIC ALIPHATIC ACID-POLYHYDRICALCOHOL RESIN Israel Rosenblum, Jackson Heights, N. Y.

No Drawing. Application December 6, 1933,

Serial No. 701,181

8 Claims.

The present invention relates to the production of polyhydricalcohol-fatty acid resins, and more particularly of an improved resincomposed of a polyhydric alcohol, maleic acid and one or more fattyacids of high molecular weight, such as can be obtained upon hydrolysisof a fatty oil, especially of a drying or semi-drying oil, or of a fat.

It is the object of the invention to produce homogeneous, fusible,soluble resins of practically neutral character and-pale color by theinteraction of glycerol or a polyglycerol or equivalent polyhydricalcohol, maleic acid, and a fatty acid or mixtures of fatty acidsobtained by hydrolysis of drying or nondrying oils or of fats, andcharacterized by being substantially free of uncombined hydroxyl groups,and hence possessing rapid drying qualities.

I have found that when glycerol, maleic acid and a fatty oil acid arereacted in the manner generally practiced in the art, as by heating thethree ingredients together to reacting temperatures, two separate layersare invariably formed which cannot be made to fuse together even byprolonged heating; in fact, if the mass is heated enize the mixture, thelower layer, which consists essentially of glycerol-maleic acid esters,is converted into the infusible, insoluble state and ultimately chars. 3It has already been suggested to perform the condensation of glycerol,unsaturated fatty oil acids and maleic acid by first oxidizing the fattyoil acid glycerol monoester with a current of air in the presence of adrier, and then reacting the oxidized mono-ester with maleic acid.However when it is attempted to carry out such reaction, particularlywith the use of linseed oil fatty acids, and oxidation of their partialester in the presence of a drier, it will be found that two separate 40layers are formed which persist in spite of vigorous stirring andfinally the lower layer chars. If this action is carried out withunoxidized esters, enough maleic acid being employed substantially toneutralize the partial glycerol ester, the maleic acid will go intosolution, but the reaction must be stopped while the acid number isstill high (80-100); if it is attempted to reduce the acid number byfurther heating, the mass jells and becomes infusible and insoluble incommon solat elevated temperatures in the attempt to homoguct contains alarge proportion of free hydroxyl groups and hence dries with difficultyand is generally unsuited for the manufacture of air drying or even ofbaking varnishes and enamels.

Lhave found, however, that a homogeneous resin of low acid number andsubstantially free of uncombined hydroxyl groups can be obtained byfirst reacting the glycerol with the fatty oil acid to produce thediester of such acid, and then neutralizing the remaining free hydroxylgroups with approximately the theoretical amount of maleic acid. By suchprocedure'the resin can be safely heated long enough to reduce its acidnumber to about 25 or below without danger of converting it into theinfusible state; in fact, a resin having an acid number ofonly about 3to 6 can readily be obtained with my improved procedure.

The present invention accordingly contemplates an improved process forthe manufacture of pale, quick-drying, soluble resinous materials of lowacid number by reacting a trihydric or higher alcohol, maleic acid andone or more fatty oil or fat acids in such order and in suchproportions, due allowance being made for unavoidable loss of alcoholduring'the reaction, that first the di-acid ester of the last-mentionedacid is formed, and such ester then substantially neutralized withmaleic acid, there being no quantity of remaining free hydroxylssuillcient to impair the air drying qualities of theresin when thelatter is applied as a film in a suitable solvent.

The invention will be described in greater detail with the aid of thefollowing examples which illustrate several satisfactory proceduresembodyingmy improved process.

Example 1.-1680 grs. (approximately 6 mols) of soya bean oil fatty acidsare heated to about 230-240 C. or somewhat higher with 285 grs.(approximately 3 mols') of glycerol until a glycerol diester is obtainedhaving an acid number of about 1. There are then added 1 grammolecularweights of maleic acid (174 grs.) or maleic anhydrlde (147 grs.) and theheating is continued at a temperature of 230-2402 or somewhat lower orhigher, the mass being continually stirred either. mechanically or bybubbling an inert gas therethrough. After about 15 to 20 hours heatingthe product becomes highly viscous and has an extremely low'acid number(about 4-8). The product is plastic in character at room temperatures,is soluble in mineral spirits and in varnish oils, andpresents a verydesirable resin because of its practically neutral character as it canbe mixed with basic pigments (and of course also with other types ofpigments) for the manufacture of enamels and paints. It is alsosubstantially free of hydroxyl groups and accordingly dries quickly bothin air and on baking.

Example 2.-The same procedure as set forth in Example 1 is followedexcept that instead of soya bean fatty oil acid, wood oil fatty acids orlinseed oil fatty acids, or mixtures of the different fatty oil acidsand fat acids, or the acids obtained from cotton seed oil or perilla oilare employed. There may also be employed the acids of the followingoils, either alone or in admixture: corn oil, sunflower oil, castor oil,olive oil, rapeseed oil, rubber seed oil, fish oil etc. the propertiesof the final product depending to some extent upon the character of thefatty oil acid used.

The mixed ester resins produced in accordance with the above-describedprocess are solubie also in benzol, turpentine and other common varnishsolvents.

The plastic resins above-obtained can be mixed with varnish oils or withvarnishes and impart thereto paleness of color and superior durabilityand water-proofness.

Care should be taken not to use oxidized fatty oil acids, as I havefound that the partial glycerol esters made from such acids have only aslight solvent power for maleic acid, so that a large part of the maleicacid can not be made to enter into reaction to form a neutral or nearlyneutral product, but form rather a separate layer. In addition,oxidation of the fatty acids, especially at elevated temperatures, tendsto darken the color of the product and reduces the value of the latter.

I claim:

1. The method of producing homogeneous, cilsoluble resins containingmaleic acid, which comprises reacting glycerol and one or more of theacids obtainable on hydrolysis of an oil or fat in substantially thetheoretical amount required to form the glycerol diester of such acid oracids until a product of low acid number is obtained, and then reactingsuch product with substantially the theoretical amount of maleic acidrequired to neutralize the same.

2. The method of producing homogeneous, oilaolubie resins containingmaleic acid, which comprises reacting the glycerol diester of one ormore acids obtainable on hydrolysis of an oil or fat with substantiallythe theoretical amount of maleic acid required to neutralize the same.

3. The method of producing homogeneous, oilsoluble resins containingmaleic acid, which cmprises reacting glycerol and substantially thetheoretical amount of unsaturated fatty oil acid required to form theglycerol diester of such acid until a product of low acid number isobtained, and then reacting such product with substantially thetheoretical amount of maleic acid required to neutralize the same.

4. The method of producing homogeneous, oilsoluble resins containingmaleic acid, which com-- prises reacting the glycerol diester of theacids of a drying oil with substantially the theoretical amount ofmaleic acid required to neutralize the same.

5. The method of producing homogeneous, oilsoluble resins containingmaleic acid, which 'comprises reacting two mols of glycerol with fourmols of unsaturated fatty oil acid until a product consisting primarilyof the diester of such acid and having a, negligible acid number isobtained, and then reacting such diester with one mol. of maleic acid attemperatures up to about 250 C. until an oil-soluble, homogeneousproduct is obtained.

6. The homogeneous, oil-soluble reaction product of (1) the low acidnumber product obtained by reacting approximately two mols of glyceroland four mols of a fatty acid obtainable on hydrolysis of a fatty oil orof a fat, and (2) one mol. of maleic acid.

7. The homogeneous, oil-soluble reaction product of (1) the low acidnumber product obtained by reacting approximately two mols of glyceroland four mols of drying oil acids, and (2) one mol. of maleic acid.

8. The homogeneous, oil-soluble reaction product of (1) the low acidnumber, glycerol diestercontaining product obtained by reactingapproximately 1 mol. of glycerol with two mols of the acids onhydrolysis of a fatty oil or of a fat and (2) approximately thetheoretical amount of maleic acid required toneutralize the same, saidproduct having an acid number of or below.

ISRAEL ROSENBLUM.

